The preliminary results of the research project Colonia3D are now presented to the public in the archeological exhibition „Fundgeschichten. Archäologie in Nordrhein-Westfalen“. This exhibition is the achievement of an interdisciplinary team of archaeologists, designers, and computer graphics engineers. The collaboration aims at reconstructing an high-detail virtual 3D city model of Roman Cologne. The interactive, didactical application is based on technology developed by the research group 3D Geoinformation at the Hasso-Plattner-Institute. It enables users to freely explore the historical site through a 3D overview, detailed views of on-site findings, as well as derived reconstructions. Using panoramic images, users can compare the Roman Cologne with the situation in today's Cologne.